Probably a debate that's been had many times...
Do you think Gabby would have had a career as a Premier League player if he didn't happen to come through at Villa with O'Neil as manager? I'm very unsure he'd have had any sort of top-flight career.
MON's counter attack football suited Gabby who could just sprint after hoofs and get on the end of everything. It took him about 5 or 6 years to develop much of a hold up game, which he did eventually.
For technically limited players, once the slide starts, it doesn't stop. MON's motivational skills were essential early on to get him running channels and contributing without really being about to control a pass 90% of the time.
Had he come through under a different manager, at any club, he'd have been fortunate to find anyone that suited him as much as O'Neil did.
If an 18 year old Gabby appeared now I don't think he'd get much of a look in. I think the league is much, much stronger, and far more tactical.